1. Field of the Invention
The present invention relates to an inverter case, and particularly, relates to an inverter case provided in a transaxle of a vehicle.
2. Description of Related Art
Conventionally, there has been known such a configuration that an inverter case is provided on a transaxle configured such that a motor, a transmission, and so on are integrally incorporated within a case, in a hybrid vehicle. When the inverter case is provided on the transaxle as such, a distance between the inverter and the motor is shortened. This advantageously makes it possible to easily arrange a power cable for connecting the inverter and the motor and to shorten a cable length.
For example, Japanese Patent Application Publication No. 2009-201218 (hereinafter referred to as JP 2009-201218 A) describes a hybrid driving device in which an inverter case accommodating an inverter therein is attached onto a transaxle so, as to be inclined downward toward a front direction in terms of a vehicle longitudinal direction. JP 2009-201218 A shows that, in the inverter case of the hybrid driving device, a refrigerant passage through which refrigerant such as cooling water or coolant circulates and flows is formed, and a conduit line for the refrigerant flowing through the refrigerant passage is provided in a projecting manner on a side wall portion of the inverter case on a vehicle front side.
In the meantime, in the inverter case of the hybrid vehicle or the like, a shaft seal structure is applied to the refrigerant conduit line placed on the vehicle front side so as to connect a refrigerant passage member thereto. Here, the “shaft seal structure” is a seal structure that allows the refrigerant passage member connected to the conduit line to move its axis direction, and secures a sealing state of a connection portion between the inverter case and the refrigerant passage member.
In the inverter case attached to be inclined downward toward the vehicle front side, in a case where the refrigerant passage member to which such a shaft seal structure is applied is provided on the side wall surface of the inverter case on the vehicle front side, when a front collision of the vehicle occurs, vehicle component parts such as a radiator and a hood placed closer to a front side of the inverter case move rearward so as to make contact with the inverter case, which highly possibly causes a collision load to be input into the inverter case.
In that case, if the refrigerant passage member employing the above shaft seal structure is connected to the front side wall surface of the inverter case, the refrigerant passage member that has received the collision load penetrates into the inverter case, which may damage the inverter inside the inverter case.